How to Caramelize Onions (with Recipe)

True caramelized onions are a labor of love. Many times at restaurants and various eateries, is the promise of an entree with "caramelized onions". Sometimes they really are, but usually, it's their way of making sauteed onions sound fancy. This is likely because it takes such a long time to do correctly. However, spending that time is well worth the reward. Here's how to do it:

Photo bySonja & Eric

First, select your onions carefully, as different types have unique flavor profiles that can enhance the dish you're preparing. A good "standard" onion choice is a yellow or Spanish onion, but you can also use sweet varieties like Vidalia or Walla Walla, which are softer in texture and milder in flavor. Both work well for caramelizing.

Next, choose the right pan and size. While non-stick pans can be used, cast iron or stainless steel pans are preferable for better caramelization. Make sure the pan is large enough to avoid overcrowding the onions—some overlap is fine, but too much can cause them to steam rather than caramelize. A 12-inch pan is ideal for up to 4 medium onions or 2 jumbo onions.

Slice the onions to about 1/8 inch thick; this is the perfect size for even cooking. Use a suitable fat to cook the onions. A combination of olive oil and butter works well for a rich, golden-brown finish, but choose what best complements your dish.

Preheat your pan with the butter/oil over medium heat. Add the onions and sauté for 5 to 8 minutes until they soften and start to turn golden. Reduce the heat to medium-low or low for the rest of the cooking process. Add salt at this stage to help the onions release more moisture.

Continue cooking for 40 to 45 minutes, stirring every 5 to 10 minutes, and adjust the heat as needed to prevent burning. Caramelizing onions requires time and gentle heat, so "low and slow" is key.

Finally, deglaze the pan to capture all those flavorful browned bits stuck to the bottom. Use a liquid of your choice for this step, which should be done at the end of the cooking process right before serving. However, if the onions start to burn earlier, you can deglaze with a little liquid and lower the heat to prevent burning. Then, continue with the caramelization process.

Your onions will reduce by about 1/3.

Now, without further adieu, here is a basic caremelized onion recipe to start you out:

Photo bySonja & Eric

Ingredients:

• 1 tablespoons extra-virgin olive oil
• 1 Tbl butter
• 4 medium yellow onions, halved and sliced at 1/8" thickness
• 1/2 teaspoon sea salt
• 2-3 Tbl honey bourbon or Irish whiskey*

In a 12-inch cast iron skillet, add the oil and butter and set heat to medium. When butter starts to bubble, add the onions and sauté for around 5 minutes, or until they begin to soften.

Add the salt, reduce the heat to medium-low, and cook for 45-50 minutes, stirring every few minutes, until the onions are very soft, golden brown, and fully caramelized. The total time will depend on the size of your onions and the heat of your stove.

If the onions begin to stick to the skillet, lower the heat to low. If, after 50 minutes, the onions are not yet deeply browned and you wish to speed up the process, you can slightly increase the heat to promote caramelization. Be sure to stir continuously to prevent burning.

Then, deglaze by adding the honey bourbon or Irish whiskey, and stirring to release bits at the bottom of the pan. Cook until liquid is reduced or just about evaporated. Then, remove from heat and enjoy!

*Notes:

You can substitute other liquids to deglaze in place of the alcohol. Choose something that will complement your dish: stock, apple cider or juice, balsamic vinegar, or even water.

Caramelized onions can be stored in an airtight container in the fridge for up to 1 week or frozen for up to 4 months (adequately sealed).